Hello,
I hope someone can give me some hints regarding how to start with the drawing attached.
I started many times but I didn't find a real strategy in order to solve this kind of problem.
Thanks for any help

Hi matur61, that type of model is quite difficult to produce in MoI. Like Andrei mentions above some people do produce that type of stuff in MoI but it requires a lot of persistence and steep learning curve.

The main tool to use is sweep and to try and build one sort of "tendril" of the shape at a time with different pieces that stick through each other rather than trying to build the whole thing all in one single go. Like for example you probably won't want to try and draw the full border outline and try to start with that, you need to draw some curves along the outside of each different section and sweep them.

It's overall more suited for a polygon modeler, and you might initially try one of the brush-stroke displacement programs like ZBrush or 3D-Coat.

Hi,
please look for mixed technology with "gimp"(hightmap) , "zsurf"(convert to surface) and "moi3d-tools"(manipulate surfaces), but needs a lot of exercise and fun.
........Other special programs for this technology cost a skyscraper.......

Thanks for your prompt reply.
I downloaded sculptris and saved a file in .obj (I have no other choice beside Zbrush type)
Can you suggest me how can I convert this file in order to import in moi3d ?
Thanks for your help

I think it is practically impossible to convert high polly model from Scultpris to nurbs in good quality. But there was some plugin for rhino, that some how converts high poly, I do not remeber the name of it. I thinnk it is not the best way to go. Why not to stay in poly?

> Can you suggest me how can I convert this file in order to import in moi3d ?

Sculptris works on polygon mesh data, it's a different type of model data than the NURBS surface type of data that MoI is designed to work on.

MoI can convert it's own large spline surface sheets into polygons for export by dicing them up into little pieces, but it's not so easy to go the reverse way and take already diced up little facets and convert those into larger sheets. There is some specialized reverse engineering software that can do that, but it involves quite a bit of work and the software is expensive, it tends to be more meant for helping to convert 3D scans into CAD data.

So usually if you are working with polygon mesh type data, you will not be able to bring that data into MoI. You can export polygon data out from MoI but not import it back in to MoI.

There are some exceptions to this in certain special cases like if you're working with subdivision surfaces for the polygon data and use the T-splines program to convert it, but that probably won't be an option for using with Sculptris.

So you'd mainly focus on doing your entire job in Sculptris and not bringing that object into MoI at all...

You could probably create a curve set in MoI and import that into Rhino and use TSplines to build this out, or just import the image reference into Rhino although I find the image options in MoI a little more friendly. If you want that model as NURBs it's counterproductive to model that in a poly modeler and the import it into Rhino with TSplines, just model that in Tsplines, you'll end up with a much cleaner result and you'll be able to modify that design with much less effort if you'd like to move points around.

If it's for a rendered image, modeling in polys will give you better results for less effort/time.

If you need the model to actually make a physical part, there are reasons for choosing to model in polys or nurbs

3D printing and CNC routers can use polys to make parts in plastic or wood.

If the need is to make a steel mold (ie. for injection molding, some types of casting, or stamping) or a steel part, then you will need a nurbs model. Although milling machines that cut steel can use polys, the poly model is almost universally rejected for this.